Design Patterns
Behavioral Patterns
| Pattern Name | Usage |
|---|---|
| Chain of Responsibility | Passes a request along a chain of handlers, where each handler decides either to process the request or to pass it to the next handler in the chain. |
| Command | Encapsulates a request as an object, thereby allowing for parameterization of clients with queues, requests, and operations. |
| Interpreter | Defines a representation of a language’s grammar and uses that representation to interpret sentences in the language. |
| Iterator | Provides a way to access the elements of an aggregate object sequentially without exposing its underlying representation. |
| Mediator | Defines an object that encapsulates how a set of objects interact, promoting loose coupling by keeping objects from referring to each other explicitly. |
| Memento | Captures and externalizes an object’s internal state without violating encapsulation so that the object can be restored to this state later. |
| Observer | Defines a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically. |
| State | Allows an object to alter its behavior when its internal state changes, appearing to change its class. |
| Strategy | Defines a family of algorithms, encapsulates each one, and makes them interchangeable. |
| Template Method | Defines the skeleton of an algorithm in a method, deferring some steps to subclasses. |
| Visitor | Represents an operation to be performed on the elements of an object structure without changing the classes on which it operates. |
General Tips!
- Identify Common Problems: Recognize recurring problems in your code to determine which design pattern can provide a solution.
- Understand the Principles: Familiarize yourself with SOLID principles as they often align with the motivations behind design patterns.
- Use Patterns Judiciously: Avoid overusing patterns; apply them only when they provide a clear benefit.
- Learn by Example: Study real-world examples of design patterns to see how they are implemented in practice.
- Refactor When Necessary: Don’t force a pattern from the start; refactor your code to introduce patterns when a need becomes apparent.
- Stay Flexible: Patterns are guidelines, not strict rules. Adapt them to fit your specific context.
- Document Your Design: Clearly document the use of design patterns to help future maintainers understand your design decisions.